Gun charger and recoil mechanism



June l1, i946. A. CORTE Z@ GUN CHARGER AND RECOILMECHANISM Filed Dec. 27, 1941 3 Sheets-Sheet l \o N u i s O O I u) o :j o 0 o 0 l E., l O OL JH if x l l 'I i D l 1"). x\ w r\ LO w` l. ll V n l Flc-I 4 'INVENTOR ALFRED CORTE June u, i946. A COR-rg 2,403,860

GUN CHARGER AND RECOIL MECHANISM Filed Dec. 27, 1941 sheets-sheet 2 U n n a i .E 27: 2g i2? :t 3l

I p /I H K :1 /2 L F/G--ZI n INVENTOR ALFRED COR TE June 11, w46. A A; ,CORTE 4 401,860

GUN CHARGER AND RECOIL MECHANISM Filed Dec'. 27, 1941 3 Sheets-Sheet 5.

\m 10 i? TV//////////// IN1/avro@ i ALFRED CORTE By .HGENr Patented June 11, 1946 GUN CHARGER AND RECOIL MECHANISM Alfred Corte, Glendale, Calif., assignor, by mesne assignments, to Lockheed Aircraft Corporation, a corporation of Californiau Application December 27, 1941, serial No. 424,638

This invention relates to an improved and simplified gun charger and recoil mechanism for machine guns and the like wherein an improved recoil absorber and reouperative mechanism cooperates with the gun charger to facilitate the operation of opening the breechblock of a machine gun.

Y The operation of a gun charger normally demands a very high initial force to break the bolt, after which the force required to complete the charging is comparatively less. In my proposed arrangement, the force Von the charging handle is applied relative to a xed turret structure. Since the recoil movement is also relative to the turret structure, the application of the force on the charging handle will be transmitted through the gun back to the recoil absorber so that a movement of the charging handle is reflected in a movement of ythe recoil spring of a Ymagnitude depending upon the ratio between the breaking force of the bolt and the spring constant of the recoil spring. Eventually, a point will .be reached where the compression of the counter recoil springs results in a force equal in magnitude to the breaking force of the bolt.

As soon as the bolt is broken, equilibrium between the forces no longer exists. The compressive force of the counter recoil springs are now greater than the opposing force of the bolt, so that the work which has been done on the counter recoil springs in compressing them is released to assist in the completion of the charging cycle. Thus, the high breaking force of the bolt does not appear as a locking force at the beginning of the charging stroke, but is deferred to a later phase of the stroke where full advantage can be taken of the momentum of the gun and where the conditions for exerting the maximum force are more favorable.

'Ihe recoil absorber consists of a hydraulic braking unit with a spring type return. The hydraulic braking unit employs a metering mechanism capable of being adjusted in service to compensate for temperature variation in the propervties of the hydraulic fluid or for changes in the operation of the gun.

Metering ports are located in the wall of the cylinder along 9, line parallel with the axis of Ythe cylinder and extending for the length of the stroke.,` Thus, as the piston advances into the cylinder, the number of ports available for the escape of the fluid is decreased so that for a given rate of travel of the piston, the resistance oiered by the entrapped fluid becomes greater.

A valve is situated on the outside of the cylin- 4 claims. (ol. 89-1) 2 l der and so arranged that in the fully closed position it is capable of closing oi the entire row 'of ports. This valve is pivoted at the head end of the cylinder so that it being opened, the port nearest the head of the cylinder is uncovered least, and those further away progressively more. Thus, at the beginning of the recoil stroke, when the recoil velocity is highest, the .total port open*-` ing is largest; while toward the end of the recoil stroke, when therecoil velocity islowest, the' port opening is smallest. Since theresistance offered by the absorber to the recoil is proportional to the velocity, and isin inverse function of the' total port opening, the effect of making the two decrease together .is to offer a constant resistance to the recoil of the gun throughout the recoil. By adjustment of the valve to cover the ports, the magnitude of this r'esistance'fcan be made such that the gun can be brought to a, stop in' any predetermined distance. Y'

It is accordingly an object of this invention to provide an improved and simplified charger wherein the initial operation thereof stores up energy vin'counter recoil springs of a recoil absorber to facilitate the initiation of the retraction movement of the breechbolt of a machine gun and to assist in completingthe opening movement thereof when once started.'

It is also an object of this invention to provide an improved and simplified recoil absorbing mechanism that is adjustable to compensate for "variable factors arising in the normal vuse of the gun, and wherein rthe recoil absorbing force lis proportioned to the variations in the forces throughout the recoil stroke. Thus the rapid initial recoil movement can be opposed by a progressively increasing resistance to further movement, so that the gun can be brought to asrnooth stop in the minimum distance determined by the ability oi the supporting structure to absorb the recoil energy.

It is a further object of this invention to provide an improved and simplified hydraulic recoil absorbing mechanism for machine guns and the like wherein the cushioning effect can be sub'- vstantially matched to the intensityof the recoil force by means of progressively throttled metering orifices.

It is still another object of this invention to provide an improved and simplified hydraulic recoil absorbing mechanism which can be adjustably metered to increase its resistance to recoil, and in which the adjustment has a range of movement capable of looking up the recoil mechanism.

Other and further important objects of this invention will be apparent from the disclosures in the specication and the accompanying drawings.

This invention in its preferred form is illustrated in the drawings and hereinafter more fully described.

In the drawings- Figure I is a fragmentary side elevation of a machine gun and j,its imount embodying the eatures of lthe preferred form of gun charger and recoil absorbing mechanism of this invention..

Figure II is an end view of Figure I taken from the right or rear end thereof.

Figure III is a plan View of the hydraulic recoil absorbing mechanism including lcounter recoil springs.

Figure IV is a central section on the line IV-IV of Figure III showing the hydraulic recoil vabscnbing mechanism.

Figure V is an enlarged fragmentary detail Aof the latch mechanism for the gun charger.

.As Vshown on .the Ldrawings- .The breech :of ra .machine gun iis indicated by the numeral IIL-the :inner end of the :gun barrel beinglindicated vat I I .in FigureI. V I have .chosen to show the :gun as mounted on the "shelf I2 .of a side -rnember 'I3 of ran lairplane zturret, the gun being outside of :a-ver'tical #bulkhead 'Ill shown ,in Figure LII but omitted :in Vrpart fromFigureI for clearness. Such amachine gun, fasffurnishedfor mounting,hasforwardand rear quick .detachable couplings Ii51and I6 tolmounting posts `II and I8, either xpost :being :adjustabletfor faligning the gun vertically, while the connection .of :one of the couplings I5 .or I6 to the .gun is:ad'justable sideways :for trans-verse alignment. As shown these gun sighting adiustmentsrare .both applied tothe rear fpost IEBsandI-coupling 1.16.

.The recoil mounting of this invention supports the posts "h1 =and :Inin :a beam #I8 mounted Von rocking levers pivotallyisupportedfin 'brackets .f2lI fon the turret-.shelf l2, the :arrangement being -such .that athe gun is mounted 'on-a Aparallelogram linkage whichfcauses tit `to ymove y.back and down .upon rrecoil. :Such Vrecoil movement is resisted, .and `the shock thereof iabsorbed by a hydraulic recoilanechanism:comprisingiacasng.22mountedk Y .the pivot by zcounter. recnilspings21 rmounted 3"' :It 4will ",.be vnoted vfrompliigures :III and 'IV that .thefcasing :2-2 :has a `pin-connection 28 to the pivot 16. pistons-2.9, operatingin a cylinder `3! within vthe casing 22,:has'itsfree or-outer end 3-I isimidlarlypinfconnectedto the yoke 23,-so that comiipression-'of the l'recoil-mechanism Amoves the piston 28 towards the closed end of the cylinder 30. The .chamber-.or casing 222 `embraces 'the cylinder 3e fand-,provides Va reservoir submergingthe same in liquid, Athe desired :level of y'wliich'is indicated by .alller plug 32. Y Y

.-n-seriesrof'metering port's33'are Alocated in the lwall :of the fcylinderfalongfeJ line p'arallelwiththe axis thereof. These ports extend over the length "of the .piston'stroke andere c'overedon the outy sideby:azplateityperof valve 34 pivoted 'at 3'5 ad- VJacent the :headrfenrl 'of 'the cylinder, so that the Aports are progressively restricted by a partial seating of thevalve An externally adjustable fscrew servesfto lim'it the opening o'f `the valve 3l and may 'be screwed down Atight "to seal the" 4 ports and thus lock` the recoil mechanism. In practice, I nd that a suitable Vadjustment of this screw is to seat it solidly and then back it off a quarter turn or more according to the resistance desired in the recoil mechanism. This valve can f of the piston, these Valves being fed by ports 38 outside the `iworking farea of the cylinder. The use `of thesevalvesjallows for a fairly rapid return or'counter recoil'fofthe gun to its ring position,

under .the .urging of the springs 21, and thus allows allocation of the major part of the ring -cycle to'fthe use of the recoil brake..

The gun charger comprises a handle 4U pivoted 'a bearing in the Avertical'bulkhead I4 v(Figure II.) yand having'aslever 4,! onr the igun `side :of :the

bulkhead. The lever-4I has alink v.|12 Ysupported at its Vfree end 43by ia slider44 voperatingin ia slideway 41 on'the bulkhead. The end Vportion [I3 of the -link l42 :is forked ,to Yengage -a :pin 45 associated Vwith the Vbreech bolt of the gun. The pin e5 operates in va slot 48in the receiver or breech I-vo the-gun. Whenthe slider "has been iuily retracted it -i's-engageabl'e by 'a hooked latch 45 von the inside of kvthe bulkheadywhich "latch serves to hold the breech bolt retracted or in the inoperative position. Thew active nose of :the ,latch 46 yextends through an opening i60 in the bulkhead Id, as shown in .Figure '-V rtocooperate with the 'slider 44. f. i

Since the jgun charger lever -is :mountedon thefixed bulkhead :12, while .itvoperates against a pin lmovable with 'the Agun Yin recoil, the :normally very fhigh .initial force required to break or-start 4the breech bolt will act .tofcompressthe recoil :absorber Vand the' :counter :recoil springs, .storing energy in. the latter. 'When :sufficient energy :has .been fstored .therein .by the continued movement of `the charging Jever, :and vthe result- .ing simulated recoil movement of theigun, to .overcome the locking inertia zof .the Abreech .bOlt, .the initial lmovement thereof will fbe '.-followed .through :by a combination V:of further `movement .of .the charging lever-.and fa. :return :or #energy Tre- :leasing movement tof .the :recoil absorber frandiits counter recoilsprings.

It will .thus `.be -seen @that have invented lan improved land isimplied Jgun charger and :recoil .mechanism wherein the latter .cushions iiringrecoily of .Ya machine gun while=also .aiding in .reducing the initial V`intensity I of -eiTort .required .i or :manual charging-.of thegun.

Having thus described Ymy .invention and ythe .present preferred Aembodiments thereof, I desire to emphasize lthe -f-act that many modifications may be .resorted to `in ya manner :limited .only zby a Just interpretation i of the following claims.

I claim -`as m-y invention: Y

'1. In combination with the :breech ibolt of lia machine gun movably mounted. relati'veto'al fixed structureand Jhaving a recoil absorbing fmecha- :nism incorporating resilient recupenatingY means to return fsaidgun to firing position, la gun -icharger comprising ahand'lever vfulcrum'eclt'o .fsaidixedrstructure a;slider carried by saidl xed :structure in cooperative relationship-k to `the 'breech bolt of said gun, a link from 'saidhand lever connecting to said slider, 'saidiguncharger being v-so constructed Aand 'arranged that force .controllahly applied to said hand lever tends to move said breech bolt in the direction of recoil of said machine gun whereby the resilient recuperating means of the gun recoil mechanism is adapted to absorb and build up the applied force until the breech bolt starts and thereafter returns the stored energy to assist in completing the movement of said breech bolt. l

2. In combination with the breech bolt of a machine gun movably mounted relative to a iiXed structure and having a recoil absorbing mechanism incorporating resilient recuperating means to return said gun to firlng position, a gun charger comprising a hand lever fulcrumed to said iiXed structure, a slider carried by said iixed structure in cooperative relationship to the breech bolt of said gun, a link from said hand lever connecting to said slider, said gun charger being so constructed and arranged that force applied to said hiand lever tends to move said breech bolt in the direction of recoil of said Inachine gun whereby the resilient recuperating means of the gun recoil mechanism is adapted to absorb and build up the applied force until the breech bolt starts and thereafter returns the stored energy to assist in completing the movement of said breech bolt, and latch means carried by said xed structure and adapted to engage said slider in its breech bolt retracted position.

3. Mechanism for use with a machine gun having a breech bolt comprising a recoil absorbing device for movably mounting the gun on a rela- 6 tively stationary structure and including recuperating springs for restoring the gun after recoil, land means for charging the gun comprising a hand lever fulcrumed on said structure,

linkage operatively connected with said lever,v

and a member carried by said structure for bodily movement by `the linkage and cooperating With the breech bolt so that the force applied to the hand lever tends to move the gun through the medium of the breech bolt in the direction of recoil to compress said springs and build up sufcient energy therein to start the bolt, the return movement of the springs completing movement of the breech block relative to the gun.

4. Mechanism for use with a machine gun having a breech bolt comprising a recoil absorbing device for movably' mounting the gun on a relatively stationary structure and including recuperating springs for restoring the gun after recoil, and means for charging the gun comprising a hand lever fulcrumed on saidl structure, a slider carried by said stationary structure and operatively engaged with said breech bolt, and a link connecting the hand lever and slider so that force applied tothe lever tends to move the breech bolt in the direction of recoil to compress said springs and build up energy therein until the breech bolt starts, the stored energy in the springs thereafter @assisting in completing movement of the breech bolt.

ALFRED CORTE. 

